lib: tpm: Add command to flush resources
authorMario Six <mario.six@gdsys.cc>
Wed, 11 Jan 2017 15:00:50 +0000 (16:00 +0100)
committerStefan Roese <sr@denx.de>
Wed, 1 Feb 2017 08:02:57 +0000 (09:02 +0100)
This patch adds a function to the TPM library, which allows U-Boot to
flush resources, e.g. keys, from the TPM.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
Reviewed-by: Stefan Roese <sr@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Stefan Roese <sr@denx.de>
board/gdsys/p1022/controlcenterd-id.c
cmd/tpm.c
drivers/tpm/Kconfig
include/tpm.h
lib/tpm.c

index 2c6c698fb3a7f644473803f1730308552e8e0597..1648f1334054f5ecc330822e1ec22786c33d6040 100644 (file)
 #define CCDM_AUTO_FIRST_STAGE
 #endif
 
-/* enums from TCG specs */
-enum {
-       /* capability areas */
-       TPM_CAP_NV_INDEX        = 0x00000011,
-       TPM_CAP_HANDLE          = 0x00000014,
-       /* resource types */
-       TPM_RT_KEY      = 0x00000001,
-};
-
 /* CCDM specific contants */
 enum {
        /* NV indices */
index 312503fb96f9bfaa08407b62127f611081ec4db7..625fc43d26f6056fab4f61c07098cc5715f5033b 100644 (file)
--- a/cmd/tpm.c
+++ b/cmd/tpm.c
@@ -646,6 +646,64 @@ TPM_COMMAND_NO_ARG(tpm_end_oiap)
 
 #endif /* CONFIG_TPM_AUTH_SESSIONS */
 
+#ifdef CONFIG_TPM_FLUSH_RESOURCES
+static int do_tpm_flush(cmd_tbl_t *cmdtp, int flag, int argc,
+                       char * const argv[])
+{
+       int type = 0;
+
+       if (argc != 2)
+               return CMD_RET_USAGE;
+
+       if (strcasecmp(argv[1], "key"))
+               type = TPM_RT_KEY;
+       else if (strcasecmp(argv[1], "auth"))
+               type = TPM_RT_AUTH;
+       else if (strcasecmp(argv[1], "hash"))
+               type = TPM_RT_HASH;
+       else if (strcasecmp(argv[1], "trans"))
+               type = TPM_RT_TRANS;
+       else if (strcasecmp(argv[1], "context"))
+               type = TPM_RT_CONTEXT;
+       else if (strcasecmp(argv[1], "counter"))
+               type = TPM_RT_COUNTER;
+       else if (strcasecmp(argv[1], "delegate"))
+               type = TPM_RT_DELEGATE;
+       else if (strcasecmp(argv[1], "daa_tpm"))
+               type = TPM_RT_DAA_TPM;
+       else if (strcasecmp(argv[1], "daa_v0"))
+               type = TPM_RT_DAA_V0;
+       else if (strcasecmp(argv[1], "daa_v1"))
+               type = TPM_RT_DAA_V1;
+
+       if (strcasecmp(argv[2], "all")) {
+               uint16_t res_count;
+               uint8_t buf[288];
+               uint8_t *ptr;
+               int err;
+               uint i;
+
+               /* fetch list of already loaded resources in the TPM */
+               err = tpm_get_capability(TPM_CAP_HANDLE, type, buf,
+                                        sizeof(buf));
+               if (err)
+                       return -1;
+               res_count = get_unaligned_be16(buf);
+               ptr = buf + 2;
+               for (i = 0; i < res_count; ++i, ptr += 4)
+                       tpm_flush_specific(get_unaligned_be32(ptr), type);
+       } else {
+               uint32_t handle = simple_strtoul(argv[2], NULL, 0);
+
+               if (!handle)
+                       return -1;
+               tpm_flush_specific(cpu_to_be32(handle), type);
+       }
+
+       return 0;
+}
+#endif /* CONFIG_TPM_FLUSH_RESOURCES */
+
 #define MAKE_TPM_CMD_ENTRY(cmd) \
        U_BOOT_CMD_MKENT(cmd, 0, 1, do_tpm_ ## cmd, "", "")
 
@@ -701,6 +759,10 @@ static cmd_tbl_t tpm_commands[] = {
        U_BOOT_CMD_MKENT(get_pub_key_oiap, 0, 1,
                         do_tpm_get_pub_key_oiap, "", ""),
 #endif /* CONFIG_TPM_AUTH_SESSIONS */
+#ifdef CONFIG_TPM_FLUSH_RESOURCES
+       U_BOOT_CMD_MKENT(flush, 0, 1,
+                        do_tpm_flush, "", ""),
+#endif /* CONFIG_TPM_FLUSH_RESOURCES */
 };
 
 static int do_tpm(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
@@ -750,6 +812,14 @@ U_BOOT_CMD(tpm, CONFIG_SYS_MAXARGS, 1, do_tpm,
 "  get_capability cap_area sub_cap addr count\n"
 "    - Read <count> bytes of TPM capability indexed by <cap_area> and\n"
 "      <sub_cap> to memory address <addr>.\n"
+#ifdef CONFIG_TPM_FLUSH_RESOURCES
+"Resource management functions\n"
+"  flush resource_type id\n"
+"    - flushes a resource of type <resource_type> (may be one of key, auth,\n"
+"      hash, trans, context, counter, delegate, daa_tpm, daa_v0, daa_v1),\n"
+"      and id <id> from the TPM. Use an <id> of \"all\" to flush all\n"
+"      resources of that type.\n"
+#endif /* CONFIG_TPM_FLUSH_RESOURCES */
 #ifdef CONFIG_TPM_AUTH_SESSIONS
 "Storage functions\n"
 "  loadkey2_oiap parent_handle key_addr key_len usage_auth\n"
index 7ab34ce863542904527acf710cbec9c5620e99b6..3490ee0c3b6550a14fc9f9012413ddc377141ff5 100644 (file)
@@ -82,4 +82,10 @@ config TPM_ST33ZP24_SPI
          to the device using the standard TPM Interface Specification (TIS)
          protocol
 
+config TPM_FLUSH_RESOURCES
+       bool "Enable TPM resource flushing support"
+       depends on TPM
+       help
+         Enable support to flush specific resources (e.g. keys) from the TPM.
+         The functionality is available via the 'tpm' command as well.
 endmenu
index 9a6585d3d40e1625bf90add69e40ad1001cea116..800f29c101bb17af26931a596da0da784ba13695 100644 (file)
@@ -47,6 +47,42 @@ enum tpm_nv_index {
        TPM_NV_INDEX_DIR        = 0x10000001,
 };
 
+enum tpm_resource_type {
+       TPM_RT_KEY      = 0x00000001,
+       TPM_RT_AUTH     = 0x00000002,
+       TPM_RT_HASH     = 0x00000003,
+       TPM_RT_TRANS    = 0x00000004,
+       TPM_RT_CONTEXT  = 0x00000005,
+       TPM_RT_COUNTER  = 0x00000006,
+       TPM_RT_DELEGATE = 0x00000007,
+       TPM_RT_DAA_TPM  = 0x00000008,
+       TPM_RT_DAA_V0   = 0x00000009,
+       TPM_RT_DAA_V1   = 0x0000000A,
+};
+
+enum tpm_capability_areas {
+       TPM_CAP_ORD             = 0x00000001,
+       TPM_CAP_ALG             = 0x00000002,
+       TPM_CAP_PID             = 0x00000003,
+       TPM_CAP_FLAG            = 0x00000004,
+       TPM_CAP_PROPERTY        = 0x00000005,
+       TPM_CAP_VERSION         = 0x00000006,
+       TPM_CAP_KEY_HANDLE      = 0x00000007,
+       TPM_CAP_CHECK_LOADED    = 0x00000008,
+       TPM_CAP_SYM_MODE        = 0x00000009,
+       TPM_CAP_KEY_STATUS      = 0x0000000C,
+       TPM_CAP_NV_LIST         = 0x0000000D,
+       TPM_CAP_MFR             = 0x00000010,
+       TPM_CAP_NV_INDEX        = 0x00000011,
+       TPM_CAP_TRANS_ALG       = 0x00000012,
+       TPM_CAP_HANDLE          = 0x00000014,
+       TPM_CAP_TRANS_ES        = 0x00000015,
+       TPM_CAP_AUTH_ENCRYPT    = 0x00000017,
+       TPM_CAP_SELECT_SIZE     = 0x00000018,
+       TPM_CAP_DA_LOGIC        = 0x00000019,
+       TPM_CAP_VERSION_VAL     = 0x0000001A,
+};
+
 #define TPM_NV_PER_GLOBALLOCK          (1U << 15)
 #define TPM_NV_PER_PPWRITE             (1U << 0)
 #define TPM_NV_PER_READ_STCLEAR                (1U << 31)
@@ -594,4 +630,13 @@ uint32_t tpm_get_permanent_flags(struct tpm_permanent_flags *pflags);
  */
 uint32_t tpm_get_permissions(uint32_t index, uint32_t *perm);
 
+/**
+ * Flush a resource with a given handle and type from the TPM
+ *
+ * @param key_handle           handle of the resource
+ * @param resource_type                type of the resource
+ * @return return code of the operation
+ */
+uint32_t tpm_flush_specific(uint32_t key_handle, uint32_t resource_type);
+
 #endif /* __TPM_H */
index 88f24060f00683c001e982b9365d9d098d62a2e3..fb1221472a53651251d6c8ab29b0728a28ca6169 100644 (file)
--- a/lib/tpm.c
+++ b/lib/tpm.c
@@ -645,6 +645,35 @@ uint32_t tpm_get_permissions(uint32_t index, uint32_t *perm)
        return 0;
 }
 
+#ifdef CONFIG_TPM_FLUSH_RESOURCES
+uint32_t tpm_flush_specific(uint32_t key_handle, uint32_t resource_type)
+{
+       const uint8_t command[18] = {
+               0x00, 0xc1,             /* TPM_TAG */
+               0x00, 0x00, 0x00, 0x12, /* parameter size */
+               0x00, 0x00, 0x00, 0xba, /* TPM_COMMAND_CODE */
+               0x00, 0x00, 0x00, 0x00, /* key handle */
+               0x00, 0x00, 0x00, 0x00, /* resource type */
+       };
+       const size_t key_handle_offset = 10;
+       const size_t resource_type_offset = 14;
+       uint8_t buf[COMMAND_BUFFER_SIZE], response[COMMAND_BUFFER_SIZE];
+       size_t response_length = sizeof(response);
+       uint32_t err;
+
+       if (pack_byte_string(buf, sizeof(buf), "sdd",
+                            0, command, sizeof(command),
+                            key_handle_offset, key_handle,
+                            resource_type_offset, resource_type))
+               return TPM_LIB_ERROR;
+
+       err = tpm_sendrecv_command(buf, response, &response_length);
+       if (err)
+               return err;
+       return 0;
+}
+#endif /* CONFIG_TPM_FLUSH_RESOURCES */
+
 #ifdef CONFIG_TPM_AUTH_SESSIONS
 
 /**